FlexO/ZR subrating and partial survivability

Abstract

An optical interface includes circuitry configured to operate the optical interface at a first rate, subsequent to a requirement to subrate the optical interface to a second rate, determine which services are affected, signal a partial failure for the one or more affected services, and operate the optical interface at a second rate that is less than the first rate. The optical interface can be a Flexible Optical (FlexO) or ZR interface.

What is claimed is: 
     
         1 . A coherent optical modem comprising:
 an optical interface configured to operate at a plurality of rates;   circuitry configured to
 interface a plurality of services over the optical interface, and 
 responsive to a requirement to adjust the optical interface between the plurality of rates, wherein the requirement is for any of (i) to improve margins on a current path, (ii) to support an alternative optical protection path from the current path, or (iii) the one or more services being unequipped, determine which of the plurality of services are mapped to slices or instances of the optical interface that will be unavailable after adjustment, and signal a partial failure for only the one or more affected services while maintaining operation of non-affected services of the plurality of services. 
   
     
     
         2 . The coherent optical modem of  claim 1 , wherein the plurality of services are each carried in Optical Transport Unit-C(OTUC) slices. 
     
     
         3 . The coherent optical modem of  claim 1 , wherein the plurality of services are each carried in Flexible Optical (FlexO) instances. 
     
     
         4 . The coherent optical modem of  claim 1 , wherein the plurality of services are each carried in ZR instances. 
     
     
         5 . The coherent optical modem of  claim 1 , wherein the requirement to adjust is hitless for the plurality of services besides the failed one or more services. 
     
     
         6 . The coherent optical modem of  claim 1 , wherein the circuitry includes mapping circuitry configured to map the plurality of services to the optical interface, including adjustments based on the requirement to adjust. 
     
     
         7 . The coherent optical modem of  claim 1 , wherein the plurality of services carried are in 100G increments. 
     
     
         8 . The coherent optical modem of  claim 1 , wherein the circuitry further includes
 a Digital Signal Processor (DSP);   mapping circuitry; and   Forward Error Correction (FEC) circuitry.   
     
     
         9 . The method of  claim 1 , wherein the plurality of services are each carried in ZR instances. 
     
     
         10 . The coherent optical modem of  claim 1 , wherein the signal includes an alarm indicating a partial failure of the one or more affected services. 
     
     
         11 . The coherent optical modem of  claim 1 , wherein the signal for the failed one or more services includes one or more of a partial Alarm Indication Signal (P-AIS), a partial Backward Defect Indication (P-BDI), and a partial Server Signal Fail (P-SSF). 
     
     
         12 . A method of operating a coherent optical modem comprising steps of:
 operating an optical interface that is configured to operate at a plurality of rates;   interfacing a plurality of services over the optical interface; and   responsive to a requirement to adjust the optical interface between the plurality of rates, wherein the requirement is for any of (i) to improve margins on a current path, (ii) to support an alternative optical protection path from the current path, or (iii) the one or more services being unequipped, determining which of the plurality of services are mapped to slices or instances of the optical interface that will be unavailable after adjustment, and signaling a partial failure for only the one or more affected services while maintaining operation of non-affected services of the plurality of services.   
     
     
         13 . The method of  claim 12 , wherein the plurality of services are each carried in Optical Transport Unit-C(OTUC) slices. 
     
     
         14 . The method of  claim 12 , wherein the plurality of services are each carried in Flexible Optical (FlexO) instances. 
     
     
         15 . The method of  claim 12 , wherein the requirement to adjust is hitless for the plurality of services besides the failed one or more services. 
     
     
         16 . The method of  claim 12 , wherein the steps further include mapping the plurality of services to the optical interface, including adjustments based on the requirement to adjust. 
     
     
         17 . The method of  claim 12 , wherein the plurality of services are carried in 100G increments. 
     
     
         18 . The method of  claim 12 , wherein the coherent optical modem includes
 a Digital Signal Processor (DSP);   mapping circuitry; and   Forward Error Correction (FEC) circuitry.   
     
     
         19 . The method of  claim 12 , wherein the signal includes an alarm indicating a partial failure of the one or more affected service. 
     
     
         20 . The method of  claim 12 , wherein the signal for the failed one or more services includes one or more of a partial Alarm Indication Signal (P-AIS), a partial Backward Defect Indication (P-BDI), and a partial Server Signal Fail (P-SSF).